Method of testing gas meters



Sept. 7, 1943. A. w. FULLER METHOD OF TESTING GAS METERS Filed June 24, 1942 INVENTOR umE uuEEo U R f m WWW 0m L M the small five-light capacity,

ing of such meters economically presents a problerh which hasheretofore not urement of gas flow these methods require meters to V series with meters in 'usein 1 only method i other metersQwhioh has'been attempted for the field and thence during the test and 1 J t'sPel t re l imw Patented Sept. 7 1943. isiy-i METHOD or TEsTmo oAs n'rnR s" i Alfred w. Fuller, Short {,ConsolidatedEdison York; N. Y., acorporation of New it Inc.,"New York Hills, assignor to Y Company of New York;

,; Application June 24, 1942, sesame. -3,253 teams. (01. 73-51 Ihis invention relatestoa method oftesting gas meters, and is particularly adapted for testing meters of small capacity in the field while same remain connected to theigassupply mains.

- With the gas distribution systemsof typical cities, well over 90% of the gasmeters are of and the field testsolved.

-.gas at variouspoints onthe distribution system,

and require'careful work in thetaking of time and temperature readings. "The use of test he carrieduabout and connected in the field; ordinarily requires trucks forfltransportingthe equipment, and involves uncertainties due to the changes in outdoors into different buildings! Also the "operator can never-be certainthat the test meter is continuing to maintain its accuracy when being temperature of the test meter whenbrought from thus carried around- S0 far as is knowri; the

than the useof such tes't testing of small gas: meters, has'involved passing a volume of gas through the meter 'tobe tested 'nto a1 cylinderhaving apiston actuticularly if the piston is 'not 'moved carefully at a predetermined rate. m1:

The present invention avoids the above mentioned difficulties and which ,maybe carriedgoutguickly and accurately by a, relativelyunskilled workman, and all of the required apparatus; maybe conveniently carried, about on: his person.

According to this, invention an envelope or bag while collapsed to .a

after sufficient gas iskpassedfthrough the meter into the envelope to walls of the envelope are made substantiallynone the ees? ma be made before and after theenvelope is thus inflated, so that the difference between such read ings may be compared with the known capacity of the envelope e ,Variousfurther and morespecific objects, features and advantages of the invention will appear from the detailed description given below taken in connection with the accompanying drawing which forms a part .of this specification and illustrates merely by way of example, a pre ierred' form of the invention. The invention consists in such novelfeatures as may be shown and described in connection with the apparatus herein disclosed, and also suchf novel combinations of method steps as are disclosed and. described hereinafter. e The drawing illnstrates a preferred form of the apparatus for carrying out the invention, and in which a small sized gas meter ofiive-light connectedpthrough pipe 2 running to the gas dis- ,tributi on'main through ashut-off valve When the meter is to betested, its, outlet 4 is connectedthrough suitable piping as at 5 and a shut0fi valve as atfi toj a flexibleenvelope or having a safety hose cock. 9 is also preferably interposed ahead of the shut.-

Regulations usually require that meters of this type be tested or proved on check runs .with a low rate of'flcw, for example, at one-fifthof theso-called.badged capacity of the meter. That is, if the badged capacity is 150 cubic feet per hour, then the test is tobeconducted rate of cubic feet per hour. With the apparatus of the present invention the how provides a simplemethod negligible; capacity, connected to the outlet o. the meter and there fully inflate the latter. The

i a ti sothet n fifll fl m h nv pe 11 have afixed predetermined capacity. Readand these, parts may be may be readily reduced to approximately such .rate byd nserting during the test, an orifice in the union at the meter outlet, as indicated on the drawing. The proper size of aperture for such orifice may readily be determined by wellknownmethods, and will of course depend upon the normal gas pressure of the system. It should be understoodthat this 'orificeis not used according to the present invention to measure the rate of flow, flow during but merely to reduce the rate of of the 'meter.

The parts atf5 to 9 inclusive and the orifice are all that"ordinarilyneed be carried around by the workman fortesting meters in the field, readily connected as shown,, on shutting the valve 3 and disconnectcapacity is shown at l as installed in the field,

y the test, to approximately the required small proportion of the badged capacity ductor of heat.

-. of gas normally sufiicient'tocause valve as at 3 is closed. Then-the lighted. Gas .is thus ing the gas piping from the outlet connection of the meter. I

The bag or envelope 7'. may be formed of relatively thin fiexible material which is substantially non-elastic and preferably a relatively poor con- For example, cloth made from glass fiber, or preferably leather, may be used for this purpose. .In orderfto render the material impervious togas, it is coated or impregnated with some suitable known vinyl resin composition, lacquer or other synthetic binder material of a type preferably highly resistant ;to the light oils present in the gas. A synthetic rubber composition such as that commercially knoWn' as neoprene might be used for thi ;purpose on a glass cloth bag, but I have found that a leather bag coated with any suitable oil resistant vinyl resin operating condicomposition will withstand the tions for a longer period. h

The. envelope or container 7 is referably t, formed by sewing togetherpieces ofthe cloth or leather-so shaped that When'the device is fully inflated, all of its surfaces will be smoothly and convexly curved. Hence when fully inflated under pressures of the magnitude of those present in the usual gasdistribution system, the shape will be such, considering the non-elastic character of thematerial, that there will be no uncertainty aboutthe capacityof the container. As shown in thedrawing, a spherical form is preferred, which .1

maybe made up of a plurality of segments as at IU, sewed together'alongtheir sides and sewed at their ends to circular pieces of the fabric or cloth as at I I and I2.

A gas connection may be brought through the circular piece !2, which may be sealed in respect to the pipe as bya pair of Washers is clamped in place on the inside and outside surfaces respectively of the bag, as by nuts I4.

Repeated tests have shown that the maximum change of volume of an envelope made in this manner when fully inflated by gas as in use, will be less than 1%. .This is .well within the limits of j accuracy required for the purpose. In the usual case, the envelope may be designed to. have a capacity of 2 cubic feet so as to receive a volume the proving circle pointer IE on the usual gas is marked 2 cubic feet) to make one complete revolution in filling the envelope from its completely collapsed condition to its fully inflated condition.

When the envelope 1 is to be carried by the workman from place to place, it may be readily collapsed by pushing theupper-hemisphere down into contact with the inside of phere. Then one quarter segment may be pushed into contact with the remaining quarter segment. Thereupon star ting'at theend l-I,-the-bag may be rolledup against the gas inlet nipple. Then the rolled-up bag together with the associated fittings is ready to be lcarried .inthe pocket.

The apparatus :may be used according to the following method. :Upon .arrival at a meter :installation which is .to be. tested, :the shut-off piping at the outlet of the meter isiuncoupled and replaced by the fitting as shown, withthe envelope 1. still fully collapsed, to expel allshut-off cock 6 closed. Thereupon the safety hose cock 9 is opened slightly, valve 3 is fullyopened, andthe, gas coming from the safetylhosecockis burned until the 'proving circle pointer [5 comes around (counter-clockwise) to a dial mark on the"up stroke of the pointer,"'for example the 3:00 ocloc'k mark.

meter (which the lower hemis gas or air, and with thewill be taken up,

Meters are normally so constructed that lost motion in the operating connections to this pointer when the pointer is on its up stroke. The safety hose cock 9 is noW closed. The procedure thus far will serve to provide a small light test to insure that the meter is registering at very low rates of flow, and at the same time bring th test pointer to'a' position facilitating accurate and certain I and left-open-until the envelope 1 is fully inflated,

the bag is being-collapsed and rolled up.

erable heat. Since during-the i. e., until all of the surface areas are pushed out =convexly to form 'a smooth spher and until the fprov'ing circle pointer l5 stops moving. After the'envelope is fully inflated, the proving circle pointer may be watched for a few moments to make sure that no gas is escaping from the envelope or its connections either through any leakage due to deterioration of the envelope walls or because of faulty connections. If the proving circle? pointer thus remains stationary for a few moment at apointmorethan 360 from its initial position when the bag wascollapsed, then the meter is fast and is ordered to be exchanged. If the test pointer has turned to a question estimated to be some 8;ormore short of one complete revolution, thenthe meter is considered to be over 2% slow and isordered to be exchanged. f After notingthe'readingof the test pointer, the valves 3 and 6 are closed and the inflated envelope, together withfittings 5, 6, .8 and 9, and

the orifice, are removed .and replaced by the normaloutletconnections from the meter. The envelope may be :then carried outdoors and the gas therein discharged to thexatmosphere while Since the orifice may be takenout of theoutlet upon disconnection of-the latter, the envelope may-be quicklydefiated without requiring-the gas to beexpelled through the small aperture of the orifice. V

The above method of testing eliminates any errors-due to change of volume of the gas resulting from changing humidity and temperature. Since the apparatus may all be carried on the person of the user and the envelope is composed of a substantially non-heat conductive material, it is unnecessary toallow the equipment to stand for a considerable time for temperature' conditioning Whenit is brought indoors for. use, asiiszthe case with test meters or other equipment of types capable of absorbing considtest thegas flows through 'the .meter .and :into the collapsed en.- velope under its normal IDIESSIZYE and with the low rate of flowmormallyrequired for such'tests, noerrors will occur .due :to. abnormal rate .of flow -or abnormally rapid expansion and consequent cooling of the gas, as would .be the tease if :the gas were expanded into an evacuated 1 container or forcefully sucked ainto a cylinder Ibya lpiston at an uncertain rate; If the apparatusv asapplied-has any leakage, the above describecl method ofoperation will immediately-reveal that fact. .The meter is'tested with the sameconditions under which it-norinallyoperates, and -no corrections have to be made dueto specificgra-vto timeor-atdifferentpartsof the system, g While the ap aratus "has been detail-with respect to particular preferred-examples, it -w'ill" be understood by those *skilled in V the art after understanding the "It invention that various changes and modifications 'maybe made determination of the i amount by which the reading is increased during *the subsequent test. The valve 6 is now opened union described in without departing from the spirit and scope of the invention, and it is intended therefore in the appended claims to cover all such changes and modifications. ,What is claimed as new and desired to be sei cured by Letters Patent is:

1. Method for testing gas meters while same are connected to a gas distributing system,

which comprises connecting the meter outlet to an envelope having non-elastic flexible walls of low heat conductivity and impervious to the gas, said envelope having a fixed predetermined volume when fully inflated by gas under pressures of the magnitude of those present in the distributing system, effecting such connection while the envelope is fully collapsed so as to contain no material amount of gas or other fluid, thereafter allowing gas to pass through the meter and into the envelope until the latter is fully inflated, and noting the amount by which the meter reading is increased by the passage of said gas in filling the envelope, for comparison of such amount with said fixed volume.

2. Method for testing gas meters by the use of a gas-tight flexible collapsible container with walls of low heat conductivity and which is ex to negligible capacity, which envelope is inflatable by gas pressure to a predetermined volume of a smoothly and convexly curved shape when fully inflated, thereafter allowing gas to pass through the meter and into the envelope until the latter is fully inflated, and comparing the amount by which the meter reading is increased by the passage of said gas, with the capacity of the fully inflated envelope.

4. Method for testing a gas meter, which comprises connecting the outlet thereof into a gas-tight substantially non-elastic envelope collapsed to negligible capacity, which envelope is inflatable by gas pressure to a predetermined limited volume, then passing enough gas through the meter to bring the meter register to a predetermined mark, said gas being by-passed from entering said envelope, thereafter allowing gas to pass through the meter without any such bypassing, into the envelope until the envelope is fully inflated, and comparing the amount by which the meter reading is increased during such inflation, with the capacity of the fully inflated envelope.

5. Method for testing gas meters by the use of a gas-tight flexible collapsible container which is expansible to a substantially fixed predetermined capacity when fully inflated by the gas pressure,comprising connecting the meter outlet to the container while collapsed to negligible capacity, thereafter allowing gas to pass at a rate equal to a substantially predetermined small proportion of the badged capacity of the meter,

' through the meter and into the container until the latter is fully inflated, and comparing the amount by which the meter reading is increased by the passage of said gas, with the said predetermined capacity of the container.

ALFRED W. FULLER.

CERTIFICATE OF CORRECTION. Patent No. 2,529,0l 2. September 7, 19L 5.

ALFRED w. FULLER.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, first column, line Q9, after the numeral "2" strike out the quotation marks; line 68', for"fitting" read fitting s; and second column, line 26, for"ques tion" read --position; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 26th day of October, A. D. 1915.

Henry Van Arsdale,

(Seal) Acting Commissioner of Patents.- 

